Carl Westin

6-8 Discussion 143 In both studies, the proportion of consistent controllers according to the control problem classification was equal to, or higher, than that of the solution parameter hierarchy classification for all scenarios, except Scenario 1 in Study 1. Based on open-ended questionnaire responses in Study 2, the control problem classification appears to fit well with controllers’ own conflict solving styles. Most controllers in Study 2 were also found consistent according to the control problem classification overall. Overall, the solution geometry classification had the largest proportion of consistent controllers in Study 1, as compared to the other classifications. For Study 1, consistency was overall highest according to the solution geometry classification, Consistency was only lower than the other classifications for Scenario 2. Similarly, consistency was lower for the solution geometry classification than the control problem classification in Study 2. However, of those found consistent, a majority used the same problem-solving style. 6-8-2 Conflict solution agreement Questionnaire data in Study 2 showed that the majority of controllers believed that their colleagues had solved the designed conflict differently. Their responses are supported by the large variability in solutions recorded in the simulation, and low overall agreement for the more detailed decision stages across classifications. When considering all three strategy classifications, results indicate that con- trollers largely agreed on the same solution geometry, but disagreed on how to achieve it in terms of the solution parameter hierarchy or control problem classifica- tion. This suggests that controllers strive to achieve the same spatial relationship of a solution, but adopt different methods. It is possible that controllers only consider solutions in terms of the resulting spatial relationship between aircraft and more ar- bitrarily chose which specific control actions to implement in order to achieve this goal. This reasoning is supported by previous research indicating that controllers rely on simplifying heuristics and satisficing in conflict resolution. For instance, Inoue et al. 247 found that controllers share the same or similar strategies, but that the concrete methods for solving conflicts differ individually. 6-8-3 Effects of experience on consistency and agreement Observations and informal conversations with controllers in Study 1 indicated that experience may have had an influence on controllers’ problem-solving styles. Un- fortunately, the sample composition did not provide enough data to do a compari- son. In Study 2, however, there was an opportunity to study the effects of experience on problem-solving styles, and differences in consistency and agreement between novices (i.e., trainees) and experienced controllers.